Femoral intramedullary rod system

ABSTRACT

A femoral intramedullary rod system capable of treating a variety of femoral bone fractures using a uniform intramedullary rod design. The system generally comprising an intramedullary rod defining an opening having an upper surface and a transverse member including a bone engaging portion and a connection portion defining a thru-hole with the nail sized to pass therethrough. A pin is selectively coupled to the transverse member to rigidly assemble the transverse member to the nail when the nail is passed through the thru-hole and the pin is received within the opening.

This application is a division of U.S. patent application Ser. No.09/329,688, filed on Jun. 10, 1999 now U.S. Pat. No. 6,221,074 andentitled FEMORAL INTRAMEDULLARY ROD SYSTEM; the contents of which arehereby incorporated by reference.

FIELD OF THE INVENTION

The present invention is directed to techniques for treating bonefractures. Specifically, but not exclusively, the invention relates to asystem for treating a variety of typical femoral fractures using auniform intramedullary rod design.

BACKGROUND OF THE INVENTION

The femur generally comprises an elongated shaft extending from the hipto the knee. The proximal end of the femoral shaft includes a necksegment connected to a head portion. The head portion fits into aconcavity of the hip bone to form a ball and socket joint at the hip.The distal end of the femoral shaft engages the upper end of the tibiato form the knee joint. Overall, the femur is one of the longest andstrongest bones in the human body; however, portions of the femur areextremely susceptible to fracture.

Internal fixation of femoral fractures is one of the most commonorthopedic surgical procedures. Many different types of femoralfractures are encountered in practice, including fractures of thefemoral neck, midshaft, and distal regions. When the femur is fractured,treatment requires that the fractured bone be substantially immobilizedand held together in an abutting relationship during the healingprocess. Any longitudinal, transverse, or rotational movement of onesection of the fractured bone relative to the other can causesubstantial delay in healing time or cause improper healing to occur. Ingeneral, two different internal fixation approaches have been used toimmobilize the area surrounding the fracture site.

One approach involves driving metallic pins through the two sections ofbone to be joined and connecting them to one or more plates bearingagainst the external surface of the bones. However, such an arrangementinjures the flesh and muscle surrounding the bones and a large number ofpins driven through the bone tend to weaken its hard outer layer. Platesalso tend to stress the bone and are not always able to bear sufficientstress for many femoral fracture applications.

Further, bone beneath the plate does not always become as strong as itwould in the absence of the plate. A second approach to treating femoralfractures involves the use of an intramedullary nail which is insertedinto the medullary canal of the femur and affixed therein by a number ofdifferent methods. After complete healing of the bone at the fracturesite, the nail may be removed through a hole drilled in the proximal endof the femur. A wide variety of devices have been developed over theyears for use in the internal fixation of femoral fractures utilizingthe method of intramedullar stabilization and immobilization. Whilethere have been a number of technological advances made within the areaof intramedullary fixation of femoral fractures, several problem areasremain.

One such problem arises from the fact that most intramedullary fixationsystems currently available are adapted to a specific type of femoralfracture, resulting in a large number of highly specializedconfigurations. This has led to the disadvantageous consequence thathospitals and trauma centers have to keep a large inventory ofincremental nail lengths with varying configurations and ancillary partsin order to accommodate a random and diverse incoming patientpopulation. Maintaining such a high level of inventory to handle allexpected contingencies is not only complex, but is also very expensive.Correspondingly, the possibility of error during selection andimplantation of the fixation device by the surgeon is elevated.Likewise, the inventory costs associated with varying methods ofintramedullary fixation are drastically increased and, in the case ofsmaller medical facilities, may necessitate switching to a less costlyand potentially less effective method of treating femoral fractures.

Another problem may result from intramedullary rod systems used tospecifically treat fractures of the neck or head of the femur. Thesedevices typically include a transverse fixation member (nail, pin,screw, etc.) adapted to be positioned along the longitudinal axis of thefemoral neck with its leading end portion embedded in the femoral headso as to grip the femoral head and thereby stabilize the fracture site.The fixation member is operably connected to the intramedullary rod tomaintain a fixed relationship between the fixation member and the rod.Unfortunately, this structural connection does not always preventrotational or translational movement of the fixation member relative tothe intramedullary rod in response to forces commonly resulting from thenormal activity of a convalescing patient. Additionally, theintramedullary rods used in these devices are typically specialized foruse with this single fixation application and can not be used in otherapplications. Therefore, the costs associated with maintaining increasedlevels of inventory are substantially increased. Furthermore, if it isdesired to vary the angle of the fixation member relative to the rod,substantial modifications must typically be made to either the fixationmember or the rod member to accommodate for such an angular variation,again driving up inventory levels and associated inventory costs.

In still another problem area, on occasion, it is necessary to usetransverse locking bone screws to lock the rod into position relative tothe femur. In order to prevent the screws from backing out, locking nutscan be threaded onto the distal ends of the locking screws.Unfortunately, the installation of locking nuts onto the ends of thelocking screws requires additional surgical incisions and commonlycauses soft tissue irritation.

In yet another problem area, when an intramedullary rod is inserted intothe medullary canal and anchored to the femur by two or more bonescrews, despite the best efforts of the surgeon, the fracture site mayhave either been over-compressed or over-distracted as a result of theinsertion of the rod. Unfortunately, with conventional intramedullaryrods, it is virtually impossible to adjust the amount of distraction orcompression without first removing one or more of the bone screws andmanually distracting or compressing the fracture site. Theintramedullary rod must then be re-anchored to the femur by reinsertingthe bone screws at different positions along the femur.

Thus, there is a demand for bone treatment techniques to address theseproblems. The present invention meets this demand and provides otherbenefits and advantages in a novel and unobvious manner.

SUMMARY OF THE INVENTION

The present invention is directed to techniques for treating bonefractures. Various aspects of the invention are novel, nonobvious andprovide various advantages. While the actual nature of the inventioncovered herein can only be determined with reference to the claimsappended hereto, selected forms and features of the preferred embodimentas disclosed herein, are described briefly as follows.

One form of the present invention includes treating a bone fracture witha nail that defines an opening and a transverse member including a boneengaging portion and a connection portion. The connection portiondefines a through-hole and the nail is sized to pass through thethrough-hole. A pin is adjustably coupled to the transverse member torigidly assemble the transverse member to the nail.

In a further form of the present invention, a method of treating a bonefracture includes forming a first hole in a femur transverse to themedullary canal and introducing a transverse member through the firsthole. The transverse member includes a through-hole that is positionedrelative to the medullary canal of the femur, and is preferably alignedtherewith. The method further includes forming a second holeintersecting the medullary canal and inserting an intramedullary nailinto the medullary canal via the second hole. The nail passes throughthe through-hole of the transverse member. The nail may include anopening aligned with the transverse member to facilitate rigid assemblyto the transverse member by positioning a pin coupled to the transversemember in the nail opening.

In still another form of the present invention, a system for treatingbone fractures includes a nail having a first end portion opposite asecond end portion along a longitudinal axis. The first end portiondefines an opening extending through the nail and has an angled surfaceoriented at an oblique angle relative to the longitudinal axis of thenail. Also included is a sleeve that includes a pair of aperturespositioned on opposite sides of the sleeve. The apertures and theopening align to form a passageway when the sleeve is fitted over an endportion. A bone engaging member is received within the passageway in anabutting relationship with the angled surface.

In yet another form of the present invention, a bone fracture treatmentapparatus includes an elongated nail having a longitudinal axis and atransverse axis generally perpendicular to the longitudinal axis. Thenail defines a transverse opening extending along the transverse axiswith the opening being bound by an upper surface and an opposite lowersurface. At least one of the upper or lower surface defines a projectionextending in a longitudinal direction to thereby narrow a dimension ofthe opening within the nail. The nail opening, and projection may bearranged to cooperate with one or more other members suitable to treat aparticular type of bone fracture, such as a fracture of the femur.

According to another form of the present invention, a system fortreating bone fractures includes a nail defining a longitudinal axis, atransverse axis and an opening extending along the transverse axis withthe opening being bound by a bearing surface. Also included is a sleevehaving a pair of apertures positioned on opposite sides thereof. Theapertures and the opening are aligned to form a passageway when thesleeve is fitted over the nail. A bone engaging member is sized to passthrough the passageway. Additionally, the system may include a means forbiasing the sleeve in a longitudinal direction to clamp the boneengaging member against the bearing surface.

Still a further form of the present invention includes a technique fortreating bone fractures with a nail that defines a longitudinal axis, anelongated opening extending therethrough, and a longitudinal passageintersecting the opening. A bone engaging member passes through theopening and a positioning device is provided that may be adjusted tochange position of the bone engaging member along the longitudinal axisrelative to the nail when the member is positioned through the nailopening. This device may be utilized to facilitate compression ordistraction of a bone fracture.

Accordingly, one object of the present invention is to provide animproved bone fracture treatment system. Preferably, this system may beused to treat fractures of the femur.

Additionally or alternatively, another object is to provide an improvedmethod of treating bone fractures, particularly fractures of elongatedbones such as the femur.

Additionally or alternatively, still another object is to reduce thecomplexity and inventory costs associated with treating bone fractures.

Other objects, features, forms, embodiments, aspects, advantages andbenefits of the present invention will become apparent to persons ofordinary skill in the art from the following written description andaccompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view, partly in section, of a rod system of the presentinvention with a transverse member shown in an antegrade position.

FIG. 2 is a side view, partly in section, of the system of FIG. 1 withthe transverse member in a retrograde position.

FIG. 3 is a partial side view of the proximal end portion of the rod ofFIGS. 1 and 2.

FIG. 4 is a partial side view of the sleeve of FIGS. 1 and 2.

FIG. 5 is a partial, sectional side view of the proximal end portion ofthe rod shown in FIG. 3 and the sleeve of FIG. 4 assembled together withthe locking member of FIGS. 1 and 2.

FIG. 6 is a side view, partly in section, of another rod system of thepresent invention implanted in the neck and head of a femur.

FIG. 7 is a partial, sectional side view of the proximal end portion ofthe system of FIG. 6.

FIG. 8A is a side view of the fixed angle pin of FIG. 7.

FIG. 8B is an end view of the fixed angle pin of FIG. 7.

FIG. 9 is a partial, sectional side view of the proximal end of yetanother system of the present invention having a variable angle pinpositioned at 135 degrees relative to a rod.

FIG. 10A is a side view of the leading portion of the variable angle pinof FIG. 9.

FIG. 10B is an end view of the leading portion of the variable angle pinof FIG. 9 taken along view line 10B—10B of FIG. 10A.

FIG. 11A is a side view of the trailing portion of the variable anglepin of FIG. 9.

FIG. 11B is an end view of the trailing portion of the variable anglepin of FIG. 9 taken along view line 11B—11B of FIG. 11A.

FIG. 12 is a partial, sectional side view of the proximal end of thesystem of FIG. 9 showing the variable angle pin at 140 degrees relativeto the rod.

FIG. 13 is a side view, partly in section, of still another rod systemof the present invention illustrating implantation of an intramedullarynail inserted in a retrograde direction.

FIG. 14 is a partial, sectional side view of the proximal end portion ofa farther system of the present invention.

FIG. 15 is a side view, partly in section, of another rod system of thepresent invention for performing distraction of a bone fracture.

FIG. 16 is a partial, sectional side view of the proximal end portion ofthe rod of FIG. 15.

FIG. 17 is a partial, sectional side view of the proximal end portion ofthe system of FIG. 15, illustrating a first operational position.

FIG. 18 is a partial, sectional side view of the proximal end portion ofthe system of FIG. 15, illustrating a second operational position.

FIG. 19 is a side view, partly in section, of an additionalintramedullary rod system of the present invention for performingcompression of a bone fracture.

FIG. 20 is a partial, sectional side view of the proximal end portion ofthe system of FIG. 19, illustrating a first operational position.

FIG. 21 is a partial, sectional side view of the proximal end portion ofthe system of FIG. 19, illustrating a second operational position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to the embodiments illustrated inthe drawings and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of theinvention is thereby intended, any alterations and further modificationsin the illustrated embodiments, and any further applications of theprinciples of the invention as illustrated therein being contemplated aswould normally occur to one skilled in the art to which the inventionrelates.

FIGS. 1-2 depict intramedullary system 10 according to one embodiment ofthe present invention. System 10 is shown implanted in femur 12 andincludes an elongated intramedullary rod or nail 14, sleeve 16 and boneengaging member 18. System 10 also includes fasteners 20 and lockingbone screws 22 a, 22 b. FIG. 1 illustrates system 10 as used in a firstlocking configuration with bone engaging member 18 placed in anantegrade direction within femur 12. FIG. 2 illustrates a second lockingconfiguration of system 10; where bone engaging member 18 is placed in aretrograde position within femur 12. The tip of the greater trochanter12 a, the neck 12 b, and the head 12 c of femur 12 are designated inFIGS. 1 and 2. Although system 10 is shown implanted in a human femur12, system 10 could also be used in conjunction with other bones aswould occur to one skilled in the art, including, but not limited to,the tibia, humerus, radius, ulna and fibula.

Nail 14 includes a proximal end portion 14 a and a distal end portion 14b. Nail 14 also defines a longitudinal centerline axis L₁ running alongthe length of nail 14 between proximal end portion 14 a and distal endportion 14 b. For application to an adult human femur, proximal endportion 14 a preferably has a diameter of about 11-13 millimeters. Thediameter of the remainder of nail 14 may vary depending upon therequirements of the fixation procedure and the surgeon's preference.While nail 14 has a generally circular cross section, other suitableshapes are also contemplated as would occur to one skilled in the art.

Referring additionally to FIGS. 3-5, portion 14 b of nail 14 definesgenerally parallel transverse bores 24 a, 24 b, each sized torespectively receive locking bone screws 22 a, 22 b therein. Distal endportion 14 b also defines transverse bore 24 c, aligned generallyperpendicular to transverse bores 24 a, 24 b and sized to receivelocking bone screw 22 c (not shown). Proximal end portion 14 a definesan opening 26 and a threaded transverse bore 28, both extending throughnail 14 generally transverse to axis L₁ from a first side 14 c to asecond side 14 d. Side 14 c generally opposes side 14 d. Proximal endportion 14 a also defines threaded longitudinal bore 29 generallyextending along axis L₁ for receiving nail insertion and extractioninstrumentation (not shown) used to guide nail 14 into and out of femur12. Nail 14 also defines a longitudinal passage 30 intersecting bore 29and extending generally along axis L₁ to allow for the optional use of aguide wire (not shown) to aid in the insertion of nail 14 into femur 12.

Referring more specifically to FIGS. 3 and 5, opening 26 is bound bylower surface 31 opposite upper surface 32. Lower surface 31 includes afirst angled surface 31 a oriented generally parallel to transverse axisT₁. Upper surface 32 includes a second angled surface 32 a offset fromfirst angled surface 31 a along axis T₁. Angled surfaces 31 a, 32 a aregenerally parallel to transverse axis T₁. Transverse axis T₁ is alignedat an oblique angle α₁ relative to longitudinal axis L₁ of nail 14.Angle α₁ is preferably in a range of about 120-150 degrees, with themore preferred angle being about 135 degrees. First angled surface 31 aand second angled surface 32 a cooperate to define pathway 33 generallyoriented at angle α₁ relative to axis L₁. First pathway 33 is sized toreceive bone engaging member 18 therethrough.

Lower surface 31 also includes a third angled surface 31 b alignedgenerally parallel to transverse axis T₂. Upper surface 32 also includesa fourth angled surface 32 b generally offset from third angled surface31 b along axis T₂ that is also generally parallel to transverse axisT₂. Comparing to FIG. 2, transverse axis T₂ is also aligned at anoblique angle α₂ relative to longitudinal axis L₁ of nail 14. Angle α₂is preferably in a range of about 120-150 degrees, with the morepreferred angle being about 135 degrees. Third angled surface 31 b andfourth angled surface 32 b cooperate to define pathway 34 generallyoriented at angle α₂ relative to axis L₁. Second pathway 34 is sized toreceive bone engaging member 18 therethrough.

First angled surface 31 a and third angled surface 31 b cooperate todefine a first projection 35 extending in a longitudinal direction whichnarrows a dimension of opening 26 within nail 14 along axis L₁.Similarly, second angled surface 32 a and fourth angled surface 32 bcooperate to define a second projection 36 extending in a longitudinaldirection generally opposite first projection 35 to further narrow adimension of opening 26 within nail 14 along axis L₁. In a preferredembodiment, each projection 35, 36 defines an apex, resulting in aconvergent-divergent throat 36 a about midway between sides 14 c and 14d of nail 14. However, first projection 35 and second projection 36could alternatively define any other geometric configuration as wouldoccur to those skilled in the art. For example, first projection 35 andsecond projection 36 could be rounded. Likewise, in other alternativeembodiments, one or more of projections 35, 36 may be absent. Whileangled surfaces 31 a, 31 b, 32 a, 32 b are generally concave tocompliment member 18, other shapes are also contemplated as would occurto those skilled in the art. For example, angled surfaces 31 a, 31 b, 32a, 32 b could be flat or have other configurations corresponding to theouter surface of bone engaging member 18.

Referring to FIG. 4, sleeve 16 of system 10 is illustrated therein.Sleeve 16 has a generally cylindrical shape and defines a proximal end16 a, a distal end 16 b and a side wall 37. Sleeve 16 is sized to fitover the proximal end of nail 14 as shown in FIG. 3. Distal end 16 b istherefore open to allow for passage of proximal end portion 14 atherethrough. Sleeve 16 also defines an inwardly tapered edge 38,terminating at distal end 16 b, to permit easy sliding of sleeve 16through bone. Proximal end 16 a defines an opening 39 to permit accessto threaded bore 29, and thus allow for passage of nail insertion andextraction instrumentation (not shown). Side wall 37 defines offsetapertures 40 a, 40 b positioned on opposite sides of sleeve 16.Apertures 40 a, 40 b are generally circular and are aligned and sized toreceive bone engaging member 18 therethrough. Side wall 37 furtherdefines opposing transverse apertures 42 a, 42 b positioned on oppositesides of sleeve 16. Apertures 42 a, 42 b are generally circular and arealigned and sized to receive fastener 20 therethrough.

Referring to FIG. 5, therein is illustrated bone engaging member 18.Bone engaging member 18 includes a proximal end portion 18a and a distalend portion 18 b. Bone engaging member 18 has a generally circular crosssection and preferably has a diameter of about 5.5-6.5 millimeters forapplications treating fractured adult human femurs. Distal end portion18 b includes a means for fixedly engaging and gripping bone 44. Boneengaging member 18 may be a bone screw having a threaded distal endportion 18 b as shown in FIG. 5, or a bone blade having distal endportion 18 b formed from a plate with a helical twist (not shown).Alternately, distal end portion 18 b may be otherwise configured forengaging bone as would occur to those skilled in the art.

As illustrated in FIG. 5, when sleeve 16 is fitted over proximal endportion 14 a of nail 14, apertures 40 a, 40 b of sleeve 16 arepositioned to align with opening 26 of nail 14, and register withpathway 33 along transverse axis T₁. Collectively, apertures 40 a, 40 band opening 26 define passageway 50 coincident with pathway 33.Passageway 50 is bound on one side by first angled surface 31 a and onanother side by second angled surface 32 a. As bone engaging member 18is slidably received within passageway 50 and guided along transverseaxis T₁, bone engaging member 18 forms an abutting relationship witheither or both of first and second angled surface 31 a, 32 a. Thisrelationship may be load bearing in nature. Bone engaging member 18 issized relative to passageway 50 so that its rotational position aboutaxis L₁ and its translational position along axis L₁ are generally fixedwhen positioned therethrough.

As illustrated in FIG. 5, when sleeve 16 is fitted over proximal endportion 14 a of nail 14, apertures 42 a, 42 b of sleeve 16 are alignedwith bore 28 of nail 14. A fastener 20 is passed through aperture 42 aand threaded into bore 28 to thereby releasably secure sleeve 16 to nail14. Another fastener 20 is passed through aperture 42 b and threadedinto bore 28 to further secure sleeve 16 to nail 14. While two fasteners20 are shown to releasably secure sleeve 16 to nail 14, it is alsocontemplated that a single fastener may be used to sufficiently securesleeve 16 to nail 14. To avoid interfering with the optional use of aguide wire (not shown) to aid in the insertion of nail 14 into femur 12,fastener 20 has a length which penetrates bore 28 far enough to securesleeve 16 to nail 14, but without obstructing longitudinal passage 30.In still other embodiments, one or more of fasteners 20, bore 28, andapertures 42 a, 42 b may not be utilized at all.

Notably, by rotating sleeve 16 180 degrees relative to nail 14, system10 may be reconfigured from an antegrade orientation of bone engagingmember 18 to a retrograde orientation, or vice-versa. Similarly,regardless of which locking configuration is used, the same componentsof system 10 can be used to treat either a left or right femur by simplyrotating sleeve 16 180 degrees relative to nail 14. As a result,apertures 40 a, 40 b of sleeve 16 are repositioned to align with pathway34 through opening 26 of nail 14 along transverse axis T₂. Collectively,apertures 40 a, 40 b and opening 26 define passageway 52 which iscoincident with pathway 34. Passageway 52 is bound on one side by thirdangled surface 31 b and on another side by fourth angled surface 32 b(see FIGS. 2 and 5). As bone engaging member 18 is slidably receivedwithin passageway 52 and guided along transverse axis T₂, bone engagingmember 18 forms an abutting relationship with either or both of thethird and fourth angled surfaces 31 b, 32 b. Preferably, thisrelationship is suitable for load bearing, and generally fixes member 18with respect to rotation about axis L₁ or translation along axis L₁.

In other embodiments of system 10, the angular alignment of boneengaging member 18 relative to axis L₁ may be varied by changing theconfiguration of sleeve 16. More specifically, apertures 40 a, 40 b canbe aligned at an angle other than α₁. In these embodiments, firstpassageway 50 does not fall along transverse axis T₁ of nail 14. Thus,as bone engaging member 18 is slidably received within first passageway50, bone engaging member 18 will contact either first projection 35 orsecond projection 36, but will not form an abutting relationship withfirst angled surface 31 a or second angled surface 32 a. However, thealternative arrangement is still suitable to fix bone engaging member 18axially and rotationally relative to nail 14.

Referring again to FIGS. 1 and 2, a femur implantation procedurecorresponding to system 10 is next described. The implant proceduregenerally includes forming a longitudinal hole into, and generallyparallel with, the medullary canal from a position slightly medial tothe tip of the greater trochanter 12 a. The longitudinal hole is sizedto receive nail 14 therethrough. Preferably, the longitudinal hole isformed by drilling. Sleeve 16 is fitted over proximal end portion 14 aof nail 14 and sleeve 16 is secured to nail 14 by threading fasteners 20into bore 28. As discussed above, system 10 can be used in either afirst or second locking configuration depending on the rotationalorientation of sleeve 16 relative to nail 14.

FIG. 1 illustrates system 10 in a first locking configurationcorresponding to an antegrade configuration for the depicted femur 12.In this first locking configuration, sleeve 16 is secured to nail 14with apertures 40 a, 40 b positioned relative to opening 26 of nail 14to define passageway 52 along transverse axis T₂. Nail 14, with sleeve16 secured thereto, is inserted through the longitudinal hole and intothe medullary canal. A transverse hole is formed through femur 12 acrossthe medullary canal corresponding to transverse axis T₂ The transversehole intersects the medullary canal and is sized to receive boneengaging member 18 therein. Preferably this transverse hole also isformed by drilling. Bone engaging member 18 is inserted into thetransverse hole and through passageway 52 formed by nail 14 and sleeve16. As a result, member 18 is preferably secured against translationalong axis L₁ or rotation about axis L₁. When received in passageway 52,member 18 generally extends between a femur entry point slightly lateralto the greater trochanter 12 a to a terminal point below the base ofneck 12 b. Generally parallel bores are formed through femur 12transverse to the medullary canal and generally perpendicular to axis L₁to align with transverse bores 24 a, 24 b of nail 14. Preferably thesebores are also formed by drilling. Nail 14 is further locked intoposition by inserting locking bone screws 22 a, 22 b through femur 12and into transverse bores 24 a, 24 b of nail 14.

FIGS. 2 and 5 illustrates system 10 in a second locking configurationcorresponding to a retrograde arrangement relative to the depicted femur12. In this second locking configuration, sleeve 16 is secured to nail14 with apertures 40 a, 40 b positioned relative to opening 26 of nail14 to define passageway 50 along transverse axis T₁. The medullary canalis accessed in generally the same manner as described in connection withFIG. 1. Nail 14, with sleeve 16 secured thereto, is inserted through thelongitudinal hole medial to the greater trochanter 12 a and into themedullary canal. A transverse hole is drilled into femur 12 across themedullary canal corresponding to transverse axis T₁ and sized to receivebone engaging member 18 therein. Bone engaging member 18 is insertedinto the transverse hole through passageway 50. So arranged, member 18generally extends through neck 12 b into head 12 c. Generally parallelbores are formed through femur 12 transverse to the medullary canal andgenerally perpendicular to axis L₁. These bores are generally alignedwith transverse bores 24 a, 24 b of nail 14. Nail 14 is further lockedinto position by inserting locking bone screws 22 a, 22 b through femur12 and into transverse bores 24 a, 24 b of nail 14.

Next, a preferred method of manufacturing nail 14 is described. Thispreferred method includes drilling a first bore through proximal portion14 a in a direction corresponding to transverse axis T₁ (aligned atangle α₁). A second bore is then drilled through proximal portion 14 acorresponding to transverse axis T₂ (aligned at angle α₂) andintersecting the first bore at a point generally corresponding to thecenterline of nail 14. The first and second bores are each sized toreceive bone engaging member 18 therethrough. The first bore therebydefines first angled surface 31 a and second angled surface 32 a, andthe second bore thereby defines third angled surface 31 b and fourthangled surface 32 b. The remaining material between lower surface 31 andupper surface 32 may then be removed to form opening 26 through nail 14,having projections 35, 36 as depicted.

FIG. 6 depicts intramedullary system 100 according to another embodimentof the present invention; where like reference numerals represent likefeatures previously described in connection with system 10. System 100is shown implanted in femur 12 and includes intramedullary rod or nail14, transverse member 102, pin 103, locking screw 104 and set crew 105.System 100 also includes locking bone screws 22 a, 22 b. Although system100 is shown implanted in human femur 12, system 100 could also be usedin conjunction with other bones as would occur to one skilled in theart, including the tibia, humerus, radius, ulna and fibula to name afew. While system 100 could be used to treat the same indications assystem 10 in the second locking configuration, as illustrated in FIG. 2and discussed above, it is preferably used for fractures of the proximalportion of femur 12, and more preferably fractures between the neck 12 band head 12 c. The same components of system 100 can be used to treateither a left or right femur by rotating transverse member 102 180degrees relative to nail 14.

FIGS. 7-12 provide additional details concerning the structure andassembly of system 100. Referring to FIG. 7, various structural detailsof transverse member 102 and pin 103 are shown therein. Transversemember 102 defines a longitudinal centerline axis L₂ and includes abarrel connection portion 106 and a bone engaging portion 108.Connection portion 106 is generally cylindrical and has a side wall 110.Side wall 110 defines a passage 112 extending generally along axis L₂.Connection portion 106 also includes a proximal portion 106 a and adistal portion 106 b. Proximal portion 106 a includes an internalthreaded portion 114 extending along a portion of passage 112. Distalportion 106 b defines an external inward taper 116 to promote ease ofmovement through bone when transverse member 102 is advanced into femur12. Distal portion 106 b also defines an inner retaining lip 118 forprovisionally maintaining bone engaging portion 108 in slidingengagement with connection portion 106, the operation of which willbecome apparent hereinafter.

A thru-hole 120 is formed through connection portion 106. Thru-hole 120is generally cylindrical and has a diameter slightly greater than theouter diameter of proximal portion 14 a of nail 14. Alternately,thru-hole 120 could be elliptical or any other shape corresponding toproximal portion 14 a of nail 14. Additionally, thru-hole 120 andportion 14 a of nail 14 could be asymmetrical and of similar profile toprevent rotational movement of transverse member 102 relative to nail 14when proximal portion 14 a is received within thru-hole 120. Similarly,if thru-hole 120 and portion 14 a of nail 14 where both tapered in thesame direction and at about the same angle, the resulting tightengagement between transverse member 102 and nail 14 would aid inpreventing rotational movement.

Thru-hole 120 is formed through connection portion 102 to provide aselected angular relationship with axis L₁ when nail 14 passestherethrough. This relationship corresponds to angle α₃ between axes L₁and L₂, and is preferably in a range of about 130-145 degrees. Morepreferably, for system 100, angle α₃ is about 135 degrees and is equalto angle α₂ as depicted in FIG. 6. As will become apparent from laterdiscussion, angle α₃ corresponds to the angle of fixation betweentransverse member 102 and nail 14.

Bone engaging portion 108 includes a proximal portion 108 a and a distalportion 108 b. A bone engaging and gripping thread 122 is formed ondistal portion 108 b. Additionally or alternatively, a different bonegripping means may be utilized, such as a bone blade having distalportion 108 b formed from a plate with a helical twist, or such othermeans as would occur to those skilled in the art.

Proximal portion 108 a includes a hex recess 124 for receiving a drivingtool (not shown), such as an Allen wrench, preferably suited to drivebone engaging portion 108 into neck 12 b and head 12 c of femur 12. Boneengaging portion 108 defines a longitudinal passage 126 extendingtherethrough and generally along axis L₂ to allow for the optional useof a guide wire (not shown) to aid in the insertion of bone engagingportion 108 into bone. Proximal portion 108 a is sized to be receivedwithin passage 112 of connection portion 106 to allow slidable movementof bone engaging portion 108 generally along axis L₂ over apredetermined range. A keeper 128 is provided on, in association with,or integral to proximal portion 108 a to provisionally maintain boneengaging portion 108 and connection portion 106 in a telescopic slidingrelationship. Keeper 128 is comprised of a cylindrical sleeve that ispreferably laser welded onto shaft 130 of bone engaging portion 108after it has been positioned within connection portion 106. The outerdiameter of keeper 128 is slightly smaller but in close tolerance withthe inner diameter of passage 112.

Pin 103 is shown positioned within passage 112 of connection portion106. FIGS. 8A and 8B additionally illustrate various structural detailsof pin 103. Pin 103 has a longitudinal centerline axis L₃ and includes aleading portion 132 integrally connected to a trailing portion 134.Leading portion 132 has a generally circular, elongated body and issized to be received within opening 26 of nail 14. Leading portion 132also includes an angled, annular engaging surface 135 configured toco-act with a surface of nail 14. Engaging surface 135 is aligned at anangle α₄ relative to axis L₃. Angle α₄ is in a range of about 130-145degrees. Most preferably, angle α₄ should be approximately equal toangle α₂. Leading portion 132 additionally includes a tapered tip 136.Trailing portion 134 is provided with an externally threaded portion 137configured to threadedly engage threaded portion 114 of connectionportion 106. A hex recess 138 is defined by trailing portion 134 forreceiving a driving tool (not shown), such as an Allen wrench, toadvance pin 103 into portion 106 or remove pin 103 from portion 106 byturning in a corresponding rotational direction. In other embodiments,pin 103 additionally or alternatively has a different means forpositioning relative to connection portion 106, such as a ratchetingmechanism, a cabling arrangement, or any other method capable ofadvancing pin 103 along axis L₂ as would occur to those skilled in theart.

In order to prevent pin 103 from migrating once positioned in a desiredposition within passage 112, system 100 includes locking screw 104.Locking screw 104 is provided with external threads 142 configured tothreadedly engage threaded portion 114 of connection portion 106. A hexrecess 144 is defined by trailing end 146 for receiving a driving tool(not shown), such as an Allen wrench, to rotationally advance lockingscrew 104 along connection portion 106. Locking screw 104 is axiallyadvanced along axis L₂ until it tightly engages trailing portion 134 ofpin 103. In other embodiments, system 100 additionally or alternativelyincludes another locking means as would normally occur to one skilled inthe art to prevent pin 103 from migrating relative to connection portion106.

To further aid in preventing pin 103 from rotating, loosening ormigrating once positioned in a desired axial position within passage112, system 100 includes set screw 105. Set screw 105 includes athreaded portion 150 and an elongated stem portion 152. Threaded portion150 is configured to threadedly engage bore 29 of nail 14. Threadedportion 150 also includes a hex recess 154 for receiving a driving tool(not shown), such as an Allen wrench, to rotationally advance set screw105 along bore 29. Elongated stem portion 152 is sized to be slidablyreceived within longitudinal passage 30 of nail 14. Stem 152 alsodefines a tapered or contoured end 156 conforming with an outer surfaceof leading portion 132 of pin 103 to provide improved mechanicalinterlocking between set screw 105 and pin 103.

Referring generally to FIGS. 6, 7, 8A, and 8B, another embodiment of afemur implantation procedure in accordance with the present invention isdescribed with respect to system 100. This femur implantation proceduregenerally includes forming a transverse passage into femur 12 thatcrosses the medullary canal and is sized to receive transverse member102 therein. Preferably, this transverse passage is formed by drillingand begins at the lateral side of femur 12, extends into neck 12 b andterminates in head 12 c to orient transverse member 102 as depicted inFIG. 6. Also shown in FIG. 6, it is preferred that the transversepassage form an oblique angle approximately the same as angle α₃ withrespect to axis L₁ or the medullary canal.

Next, transverse member 102 is introduced through the transverse passagewith thruhole 120 positioned to at least overlap the medullary canal offemur 12, and preferably to be generally centered with respect to themedullary canal of femur 12. At least a portion of bone engaging portion108 is threaded into femur 12 at this stage. Preferably, bone engagingportion 108 is threaded into a portion of head 12 c of femur 12 byengaging hex recess 124 with a suitable tool and turning portion 108 ina corresponding rotational direction generally about axis L₂.

Notably, bone engaging portion 108 is telescopically received withinpassage 112 of connection portion 106 to allow axial movement of boneengaging portion 108 over a predetermined range along axis L₂. Keeper128 cooperates with inner retaining lip 118 to prevent disengagement ofbone engaging portion 108 from connection portion 106. The cooperationbetween inner retaining lip 118 and keeper 128 also acts to stabilizebone engaging portion 108, thus aiding in the sliding motion of boneengaging portion 108 to provide the preferred telescopic functioning oftransverse member 102. Since connection portion 106 provisionallymaintains bone engaging portion 108 in a captive, telescopicrelationship, the alignment of bone engaging portion 108 along axis L₁is always maintained. Thus, when the procedure includes turning thread122 through neck 12 b of femur 12 and into head 12 c, head 12 c willbecome fixed in an angular relationship relative to transverse member102. By maintaining the angular alignment between neck 12 b and head 12c, and allowing them to slide telescopically relative to one another,system 100 can accommodate for changes during patient movement andexpedite the bone healing process.

After transverse member 102 is inserted, an opening is formed,preferably by drilling, into and generally along the medullary canalfrom a position slightly medial relative to the tip of the greatertrochanter 12 a and sized to receive nail 14 therethrough. Nail 14 isinserted through the longitudinal and into the medullary canal. Nail 14passes through thru-hole 120 of connection portion 106. Thru-hole 120 oftransverse member 102 receives nail 14 in a close sliding fit, therebypermitting limited axial and rotational movement of transverse member102 along axis L₁ of nail 14. Transverse member 102 is longitudinallypositioned on nail 14 so that passage 112 of connection portion 106registers with opening 26 of nail 14. If desired, bone engaging portionis further advanced into the bone at this stage.

Next, pin 103 is axially advanced through passage 112 by engaging hexrecess 144 with an appropriate tool and rotating in a correspondingdirection. As threaded portion 137 of pin 103 engages threaded portion114 of connection portion 106, leading portion 132 is slidably receivedwithin opening 26 to engage one or more surfaces 31 b, 32 b. Even ifpassage 112 and opening 26 are misaligned, in many instances tapered tip136 allows pin 103 to self-center, thereby aiding in the insertion ofleading portion 132 within opening 26. As pin 103 is slidably receivedwithin pathway 34 of opening 26 and guided along transverse axis T₂,leading portion 132 forms an abutting relationship with one or both ofangled surfaces 31 b, 32 b. Pin 103 thus becomes oriented at angle α₂relative to axis L₁, aiding in the fixation of transverse member 102relative to nail 14. As pin 103 is further advanced through passage 112,engaging surface 135 is firmly pressed against nail 14 and transversemember 102 is pulled in a proximal direction. Correspondingly, an innersurface of transverse member 102 that borders thru-hole 120 is clampedagainst an outer surface of nail 14 while generally maintaining angle α₂of transverse member 102 relative to axis L₁.

After securely clamping transverse member 102 and nail 14 together,generally parallel passages are formed, preferably by drilling throughfemur 12 transverse to the medullary canal and aligned with transversebores 24 a, 24 b of nail 14. Nail 14 is further locked into position byinserting locking bone screws 22 a, 22 b through femur 12 and intotransverse bores 24 a, 24 b of nail 14.

Referring to FIG. 9, system 160 of another embodiment of the presentinvention is illustrated; where reference numerals like those ofprevious embodiments refer to like features. System 160 includestransverse member 102′ which is the same as transverse member 102 exceptthat pin 103′ is utilized in place of pin 103. FIGS. 10A, 10B, 11A and11B illustrate selected details of pin 103′. Pin 103′ includes a leadingportion 162 and a non-integral trailing portion 164. Leading portion 162preferably has a generally circular, elongated body and is sized to bereceived within opening 26 of nail 14. Leading portion 162 also includesan angled, annular engaging surface 165 configured to co-act with asurface of nail 14. Engaging surface 165 is aligned at an angle α₄relative to axis L₄ of pin 103′. Leading portion 162 additionallyincludes a tapered tip 166.

Leading portion 162 is articulated to trailing portion 164 to facilitatepivotal movement of portion 162 relative to portion 164. Trailingportion 164 includes externally threaded portion 167 configured tothreadedly engage threaded portion 114 of connection portion 106. A hexrecess 168 is defined by trailing portion 164 for receiving a drivingtool (not shown), such as an Allen wrench, to advance pin 103′ axiallyalong connection portion 106. In other embodiments, pin 103′ isalternatively or additionally configured with a different means to beaxially advanced through connection portion 106, such as a ratchetingmechanism or a cabling arrangement. In still other embodiments,techniques are utilized as would occur to one skilled in the art.

Leading portion 162 has a longitudinal centerline axis L₄ and trailingportion 164 has a longitudinal centerline axis L₅. Unlike pin 103,leading portion 162 and trailing portion 164 are not integral and arecoupled to permit leading portion 162 to pivot relative to trailingportion 164. This pivoting or articulation permits angular variation ofportion 162 relative to axis L₂. In one preferred embodiment, leadingportion 162 includes a ball and socket joint 170 to provide the angularadjustment capability.

The rear portion of leading portion 162 defines a concave surface 174generally centered about axis L₄. Projecting proximally from concavesurface 174 along axis L₄ is stem 178. Stem 178 has a generally circularcross section, but also preferably defines a pair of parallel, opposingflats 180 a, 180 b. A ball member 182 is positioned at the end of stem178 and is generally spherical-shaped. Trailing portion 164 defines aconvex surface 184 generally centered about axis L₅ and configured toclosely conform with concave surface 174 of leading portion 162.Trailing portion 164 also defines a transverse socket 186 extendingpartially therethrough and aligned generally perpendicular to axis L₅.

Transverse socket 186 has a diameter slightly larger than the diameterof ball member 182. Transverse socket 186 terminates at concave bottomsurface 188. Concave bottom surface 188 substantially conforms with theouter surface of ball member 182. Trailing portion 164 also defines alongitudinal bore 190 aligned with axis L₅. Longitudinal bore 190extends from convex surface 184 to transverse socket 186. Longitudinalbore 190 is outwardly tapered with wide end 190 a intersecting convexsurface 184 and narrow end 190 b intersecting transverse socket 186,thus defining taper angle α₅ relative to axis L₅. Preferably, taperangle α₅ is between about 5 degrees and 20 degrees. Most preferably,taper angle α₅ is about 10 degrees. Trailing portion 164 further definesa transverse slot 192 extending partially therethrough and substantiallyaligned with transverse socket 186. Slot 192 has a width W extendingalong longitudinal bore 190 from convex surface 184 to transverse socket186. Slot 192 has a depth sufficient to intersect narrow end 190 b oftransverse bore 190. Height H of slot 192 is slightly greater than thedistance between flats 180 a, 180 b of stem 190. Collectively, socket186 and slot 192 are configured to receive ball member 182 and stem 178therein, respectively.

In another embodiment of pin 103′, a flexible, readily deformableintermediate section is positioned between leading portion 162 andtrailing portion 164 that may be additionally or alternatively used toprovide means for allowing angular variation between axis L₄ and axisL₅. In still another embodiment, portion 162 is journaled to portion 164by a shaft through a bore, permitting rotation of portion 162 relativeto portion 164. In other embodiments, another suitable means forproviding angular variation between axis L₄ and L₅ may alternatively oradditionally be utilized as would occur to those skilled in the art.

As illustrated in FIG. 9, pin 103′ operates generally in the same manneras pin 103 described in connection with system 100. Although pin 103′can be used in instances where angles α₂ and α₃ are substantially equal(as shown in FIG. 9), the more preferred application arises inconfigurations where angles α₂ and α₃ are different. The articulation ofleading portion 162 relative to trailing portion 164 facilitates secureclamping to nail 14 despite a mismatch between the angled surfaces 31 a,32 a, or 31 b, 32 b and the angular relationship of member 102′ to axisL₁ defined by thru-hole 120. For example, referring additionally to FIG.12, angles α₂ and α₃ are about 135 and 140 degrees, respectively,relative to axis L₁. Preferably, the pivot range of leading portion 162accommodates a range of different angular orientations of thru-hole 120corresponding to α₃. In one more preferred range, leading portion 162pivots to accommodate a variation of angle α₃ from about 130 to about145 degrees.

In one preferred implantation procedure, transverse member 102′ and nail14 are implanted in accordance with the same procedure for insertingbone engaging member 108, connection portion 106 and nail 14, with theengagement of pin 103′ in place of pin 103. For pin 103′, ball member182 is inserted into socket 186 by aligning flats 180 a, 180 b of stem178 with slot 192 and then guiding ball member 182 within transversesocket 186 until ball member 182 is positioned adjacent concave bottomsurface 188. A slight rotation or angulation of leading portion 162relative to trailing portion 164 securely engages the two portions. As aresult, leading portion 162 is rotatably coupled to trailing portion 164by ball and socket joint 170. Thus, leading portion 162 can rotatefreely over a predetermined range within passage 112 as limited by taperangle α₅. In one preferred embodiment, taper angle α₅ permits angularvariation between leading portion 162 and trailing portion 164 of about10 degrees in any direction. The assembly of leading portion 162 totrailing portion 164 may be performed during the implantation procedurejust before insertion into passage 112 or in advance of the procedure asdesired.

Once leading portion 162 and trailing portion 164 are assembled, Pin103′ is advanced through passage 112 of connection portion 106 byengaging hex recess 168 and turning in the appropriate rotationaldirection. Pin 103′ is slidably received within pathway 34 of opening 26and leading portion 162 is guided along transverse axis T₂ to form anabutting relationship with one or both of angled surfaces 31 b, 32 b.If, as mentioned above, thru-hole 120 is disposed in connection portion106 in correspondence to a different angle α₃ relative to axis L₁ (suchas 140 degrees), leading portion 162 is forced to pivot relative totrailing portion 164 and thereby aligns at angle α₂ (such as 135degrees). As trailing portion 164 is tightened in connection portion106, a rigid, secure construct forms between transverse member 102′ andnail 14 as described in connection with the operation of system 100,except that pin 103′ may pivot, contacting an inner surface ofconnection portion 106 as illustrated in FIG. 12. Notably, like system10, system 100 and 160 may be reconfigured to accommodate either theleft or right femur or an antegrade or retrograde application; however,in other embodiments of the present invention, rod 14 may be modified todefine only one generally linear pathway therethrough.

Referring now to FIG. 13, system 195 according to another embodiment ofthe present invention is illustrated; where reference numerals ofpreviously described embodiments refer to like features. Preferably,system 195 is implanted in femur 12 as shown, and includesintramedullary rod or nail 14, set screw 105, and locking bone screws 22a, 22 b, 22 c. In other embodiments, system 195 may be used inconjunction with other bones as would occur to one skilled in the art,such as the tibia, humerus, radius, ulna, or fibula to name a few.Additionally, the same components of system 195 can be used to treateither a left or right femur by simply rotating nail 14 180 degreesrelative to longitudinal axis L₁. Unlike systems 10, 100 and 160; system195 positions nail 14 with the proximal and distal end portions reversedwithin femur 12 corresponding to implantation of nail 14 in a retrogradedirection. Unlike existing systems, nail 14 need not be modified tooperate in a retrograde direction. Indeed, nail 14 may be used in eitheran antegrade direction, as illustrated in connection with systems 10,100, and 160, or a retrograde direction as illustrated in FIG. 13.

One preferred implant procedure for system 195 includes forming alongitudinal hole along femur 12, intersecting the medullary canal froma point generally central to distal end portion 12 d. The longitudinalhole is sized to receive nail 14 therethrough and is preferably formedby drilling into femur 12. Nail 14 is inserted through the longitudinalhole and into the medullary canal. A pair of generally parallel,transverse passageways are formed, preferably by drilling, through femur12 transverse to and intersecting with the medullary canal. Thesepassageways are in registry with opening 26 and transverse bore 28,respectively. Nail 14 is locked into position by inserting locking bonescrews 22 a, 22 b into the transverse passageways and correspondinglythrough opening 26 and transverse bore 28. Another transverse passagewayis drilled through femur 12 across the medullary canal and intersectingtherewith that is generally aligned with transverse bore 24 c formed indistal portion 14 b of nail 14. Nail 14 is further locked into positionby inserting locking bone screw 22 c into this distal transversepassageway and correspondingly through transverse bore 24 c. Althoughsystem 195 does not require a sleeve to lock bone screws 22 a, 22 b intoposition relative to nail 14, as discussed below, such a feature mayoptionally be utilized.

Referring now to FIG. 14, shown is bone treatment system 200 accordingto yet another embodiment of the present invention; where referencenumerals of previously described embodiments refer to like features.System 200 is shown implanted in femur 12 and includes intramedullarynail 14, sleeve 202, bone engaging members 204, 205 and biasing sleeve202. Preferably, system 200 is utilized to treat fractures of the humanfemur, but may be used in conjunction with any other bone as would occurto those skilled in the art. Additionally, while system 200 can be usedwith any nail and sleeve configuration, it is preferably used inconjunction with retrograde implantation of nail 14 as described inconnection with FIG. 13 herein.

In FIG. 14, opening 26 extends generally along transverse centerlineaxis T₃ and transverse bore 28 extends generally along transversecenterline axis T₄. Opening 26 is bounded by a bearing surface 26 a andbore 28 is bounded by a bearing surface 28 a. Sleeve 202 has a generallycylindrical shape and defines a proximal end 202 a, a distal end 202 b,and a side wall 208. Sleeve 202 is sized to fit over proximal endportion 14 a of nail 14. Distal end 202 b is therefore open to allow forpassage of proximal end portion 14 a. Sleeve 202 defines an inwardlytapered edge 210, terminating at distal end 202 b, to facilitatemovement of sleeve 202 through bone. Proximal end 202 a is also open toallow for the passage of nail insertion and extraction instrumentation(not shown). The interior surface of side wall 208 immediately adjacentproximal end 202 a defines a threaded portion 211. Side wall 208 alsodefines two sets of opposing apertures 212 a, 212 b and 214 a, 214 b.Apertures 212 a, 214 a oppose apertures 212 b, 214 b in a directionalong axes T₃, T₄, respectively. Aperture sets 212 a, 212 b, and 214 a,214 b are generally circular and are aligned and sized to respectivelyreceive bone engaging members 204, 205 therethrough. Apertures 212 a,212 b define circumferential engaging surfaces 213 a, 213 b,respectively, and apertures 214 a, 214 b define circumferential engagingsurfaces 215 a, 215 b, respectively.

Bone engaging member 204 includes a proximal end portion 204 a oppositea distal end portion 204 b. Bone engaging member 204 has a generallycircular cross section and preferably has a diameter of about 5.5-6.5millimeters for a femur application. Distal end portion 204 b includesthread 216 for engaging and gripping bone. Alternatively oradditionally, member 204 may include a different bone engaging orgripping means such as a bone blade having distal end portion 204 bformed from a plate with a helical twist or an expansion device. Boneengaging member 205 includes a proximal end 205 a and a distal end 20 band is preferably configured the same as bone engaging member 204.

System 200 includes biasing end cap 220. End cap 220 is generallycircular and includes a first threaded portion 222 configured tothreadingly engage threaded portion 211 of sleeve 202. A second threadedportion 224 is configured to threadingly engage longitudinal bore 29 ofnail 14. End cap 220 proximally terminates in an enlarged, flat endportion 226 having protruding flange 228. Flat end portion 226 alsodefines hex recess 230 for receiving a driving tool (not shown).

System 200 is utilized in accordance with one preferred femurimplantation procedure by inserting nail 14 as described in connectionwith FIG. 13, except, proximal end 14 a also carries sleeve 202 thereonby loosely threading end cap 220 into sleeve 202 and rod 14.

Accordingly, protruding flange 228 of flat end portion 226 bears againstproximal end 202 a of sleeve 202. With sleeve 202 so oriented, apertures212 a, 212 b are generally in alignment with transverse bore 28 alongaxis T₄ to define passageway 232. Correspondingly, apertures 214 a, 214b are generally aligned with opening 26 along transverse axis T₃ todefined passageway 234.

Once the nail 14 and sleeve 202 are in place within femur 12, twotransverse passages are formed through the bone that are in registrywith passageways 232, 234. Next, bone engaging members 204, 205 arereceived through the bone and passageways 232, 234, respectively. Oncebone engaging members are in place. Sleeve 202 is biased by furthertightening of end cap 220. As end cap 220 is tightened, is moves sleeve202 and nail 14 in opposite directions along axes L₁. Correspondingly,surfaces 213 a, 213 b move to bear against bone engaging member 204 andengaging surfaces 214 a, 214 b bear against bone engaging member 205. Inturn, bone engaging member 204 is tightly clamped against bearingsurface 26 a of opening 26 and bone engaging member 205 is tightlyclamped against bearing surface 28 a of bore 28. The tight engagementbetween bone engaging members 204, 205 and bearing surfaces 26 a, 28 athereby clamps bone engaging members 204, 205 into position relative tonail 14 and prevents lateral migration. Locking nuts, which have in thepast been used to prevent such lateral migration, are generally notneeded for system 200, so that additional surgical incisions normallyrequired to engage locking nuts onto the bone engaging members need notbe made and soft tissue irritation commonly associated with the presenceof the locking nuts is also eliminated. Preparations and implantation ofone or more bone engaging members may optionally be performed at distalend 14 b of nail 14.

In an alternative embodiment, end cap 220 does not include firstthreaded portion 222. Thus, as threaded portion 224 engages longitudinalbore 29 of nail 14, flange 228 of flat end portion 226 contacts proximalend 202 a of sleeve 202 to advance sleeve 202 in a distal directionrelative to nail 14. In still another embodiment, end cap 220 does notinclude second threaded portion 224. Thus, as threaded portion 222engages threaded portion 211 of sleeve 202, flat end 222 a of threadedportion 222 is forced into contact with the proximal end of nail 14,thereby advancing sleeve 202 in a proximal direction relative to nail14. In yet another embodiment of system 200, the biasing means consistsof a spring member operably captured between nail 14 and sleeve 202. Thespring member is configured to urge sleeve 202, nail 14, or both toclamp bone engaging members 204, 205.

Referring now to FIG. 15, intramedullary system 300 according to stillanother embodiment of the present invention is illustrated; wherereference numerals of previously described embodiments refer to likefeatures. System 300 is shown implanted in femur 12 and includeselongated intramedullary nail 302, positioning device 304, bone engagingmember 306 and locking bone screw 308. Femur 12 includes a fracture site301, separating femur 12 into two portions 12 f, 12 e. Fracture site 301is shown in a compressed state (i.e., portions 12 f, 12 e are beingpushed together). Although system 300 is shown implanted in femur 12,system 300 could also be used in conjunction with other bones such asthe tibia, humerus, radius, ulna and fibula to name a few. Additionally,the same components of system 300 can be used to treat either a left orright femur by simply rotating nail 302 180 degrees relative to axis L₆.Although FIG. 15 illustrates nail 302 implanted within femur 12 in aretrograde direction, it is understood that system 300 could also beimplanted with nail 302 in an antegrade direction.

FIGS. 15 and 16 show various structural details of nail 302. It shouldbe understood that nail 302 can take on a number of configurations,including that of nail 14 illustrated and described above. However, in apreferred embodiment, nail 302 is configured as described below. Nail302 includes a proximal end portion 302 a and a distal end portion 302b. Nail 302 also defines a longitudinal axis L₆ running along the lengthof nail 302 between proximal end portion 302 a and distal end portion302 b. Proximal end portion 302 a preferably has a diameter of about11-12 millimeters for an adult human femur application. The diameter ofthe remainder of nail 302 can be varied depending upon the requirementsof the fixation procedure and the surgeon's preference. While nail 302has a generally circular cross section, other suitable shapes are alsocontemplated as would occur to one skilled in the art.

Nail 302 defines a passage 309 extending therethrough along axis L₆ lineto allow for the optional use of a guide wire (not shown) to aid in theinsertion of nail 302 in femur 12. Distal end portion 302 b definesparallel transverse bores 310 b, 310 c, each sized to receive lockingbone screw 308. Distal end portion 302 b also defines transverse bore310 a, aligned generally perpendicular to transverse bores 310 b, 310 cand also sized to receive locking bone screw 308.

Proximal end portion 302 a defines an elongated, longitudinal opening312 bounded by side walls 313 and sized to receive bone engaging member306 therein. Opening 312 laterally extends through nail 302 and iselongated in the direction of longitudinal axis L₆. Opening 312 has afirst end portion 312 a and an opposing second end portion 312 b.Proximal end portion 302 a of nail 302 also defines a longitudinalpassage 314 extending generally along axis L₆ and having a generallycircular cross-section. Longitudinal passage 314 intersects opening 312and terminates in a generally concave bottom surface 316. A threadedportion 318 is defined about a portion of longitudinal passage 314.Proximal end portion 302 a also defines a transverse bore 320 extendingthrough nail 302 generally perpendicular to axis L₆ and aligned withopening 312. Bore 320 is sized to receive bone engaging member 306therein.

Referring to FIG. 17 therein is shown nail 302, positioning device 304and bone engaging member 306 as assembled within system 300. Positioningdevice 304 is shown positioned within longitudinal passage 314 andincludes a first portion 322 and a second portion 324. First portion 322includes a head 326 and a threaded stem 328 extending therefromgenerally along longitudinal axis L₆. Head 326 is substantially circularand has an outer diameter generally corresponding to the outer diameterof nail 302. Head 326 also includes a hex recess 330 for receiving adriving tool (not shown), such as an Allen wrench. The diameter ofthreaded stem 328 is less than the diameter of head 326, therebydefining an annular shoulder 332.

Second portion 324 defines a generally circular, elongated body 333having a diameter slightly less than the diameter of longitudinalpassage 314. Second portion 324 also defines an internally threadedportion 334 extending generally along longitudinal axis L₆ andconfigured to threadedly engage threaded stem 328 of first portion 322.Threaded portion 334 has a depth slightly greater than the length ofthreaded stem 328. The end of second portion 324 opposite threadedportion 334 terminates into a generally convex outer surface 336 thatsubstantially corresponds to concave bottom surface 316 of longitudinalpassage 314. Second portion 324 also defines a transverse opening 338extending therethrough generally perpendicular to longitudinal axis L₆.Opening 338 is bounded by inner surface 339 and is sized to receive boneengaging member 306 therein.

FIG. 17 illustrates a first operational position of system 300.Positioning device 304 (including first and second portions 322, 324) isshown inserted within longitudinal passage 314 of nail 302. Opening 338of second portion 324 is positioned adjacent second end portion 312 b ofopening 312 and generally aligned with opening 312 to define apassageway 40. Bone engaging member 306 is shown inserted throughpassageway 340. Threaded stem 328 of first portion 322 is partiallythreadedly engaged within threaded portion 334 of second portion 324.First portion 322 can be rotated by placing a driving tool (not shown)within hex recess 330 and turning in a clockwise or counterclockwisedirection as appropriate. Second portion 324 is prevented from rotatingin correspondence with first portion 322 because of engagement betweenbone engaging member 306 against sidewalls 313 of opening 312. In oneembodiment, threaded stem 328 and threaded portion 334 each haveright-handed threads. In this embodiment, as first portion 322 isrotated in a clockwise direction, shoulder 332 of head 326 bears againstnail 302, and second portion 324 correspondingly moves toward firstportion 322 generally along longitudinal axis L₆. As the position ofsecond portion 324 is adjusted along axis L₆, inner surface 339 ofopening 338 bears against bone engaging member 306 and correspondinglyadjusts the position of bone engaging member 306 along the length ofopening 312.

FIG. 18 illustrates a second operational position of system 300 in whichfirst portion 322 is rotated in a clockwise direction until boneengaging member 306 is positioned adjacent first end portion 312 a ofopening 312. It should be understood, however, that bone engaging member306 can be variably positioned anywhere along the length of opening 312.It should further be understood that the terms “first operationalposition” and “second operational position” are not necessarilyindicative of the initial position and adjusted position of boneengaging member 306. For example, bone engaging member 306 couldoriginate in a position adjacent first end portion 312 a and be variablypositioned anywhere along the length of opening 312.

In other embodiments of system 300, nail 302 defines a keyway extendingalong the length of longitudinal passage 314 generally parallel withaxis L₆. Additionally, second portion 324 defines a key along its lengthwhich generally corresponds to the keyway defined in nail 302.Preferably, the key is radially positioned so that when it is slidablyreceived within the keyway, opening 338 of second portion 324 willcorrespondingly align with opening 312 of nail 302. Alternatively, thekey could be defined along the length of second portion 324 and,correspondingly, the keyway could be defined along the length oflongitudinal passage 314 of nail 302.

Having described selected structural and operational features of nail302 and positioning device 304, the operational characteristics ofsystem 300 will now be described in further detail. Referring back toFIG. 15, nail 302 is shown implanted in femur 12. Distal end 302 b ofnail 302 is anchored to portion 12 e of femur 12 by inserting lockingbone screw 308 into portion 12 e and through transverse bore 310 a (notshown) of nail 302. Proximal end 302 a of nail 302 is anchored toportion 12 f of femur 12 by inserting bone engaging member 306 intoportion 12 f and through passageway 340 (defined by aligning opening 338with opening 312). Preferably, bone engaging member 306 is initiallypositioned adjacent or near second end portion 312 b of opening 312. Asfirst portion 322 of positioning device 304 is rotated in a clockwisedirection, bone engaging member 306 is correspondingly repositionedalong the length of opening 312, and more specifically is transferredtoward first end portion 312 a. Because bone engaging member 306 isanchored to portion 12 f of femur 12, portion 12 f is correspondinglymoved in the direction of arrow “A”, while portion 12 e of femur 12remains stationery, securely anchored to distal end 302 b of nail 302.Thus, portion 12 f of femur 12 is repositioned away from portion 12 e,thereby distracting fracture site 301.

One preferred procedure for implanting system 300 within femur 12includes forming a longitudinal hole along the medullary canal from apoint generally central to the distal end portion 12 d of femur 12.Preferably this hole is formed by drilling sized to receive nail 302therethrough. Positioning device 304 is inserted in longitudinal passage314 of nail 302 and nail 302 is inserted through the longitudinal holeand into the medullary canal. It should be understood that positioningdevice 304 could alternatively be inserted in longitudinal passage 314after nail 302 has been implanted in femur 12. A first passage is formedthrough femur 12 transverse to the medullary canal and generally alignedwith transverse bore 310 a (not shown) formed in distal portion 302 b ofnail 302. A second passage is formed through femur 12 transverse to themedullary canal and generally aligned with passageway 340. Preferably,these transverse passages are formed by drilling. Locking bone screw 308is threaded into the first passage, passing through transverse bore 310a. Bone engaging member 306 is threaded into the second passage, passingthrough passageway 340. At this point, fracture site 301 can bedistracted by following the operational procedure described above.Dashed line 301 a of FIG. 15 corresponds to the position of thefractured end of portion 12 f after distraction in accordance with oneembodiment of the present invention.

Referring now to FIG. 19, intramedullary system 400 according to yetanother embodiment of the present invention is illustrated; where likereference numerals of previously described embodiments refer to likefeatures. System 400 is shown implanted in femur 12 and includeselongated intramedullary nail 302, positioning device 304′, boneengaging member 306 and locking bone screw 308. Femur 12 includes afracture site 301′, separating femur 12 into two portions 12 f, 12 e.Fracture site 301′ is shown in a distracted state (i.e., portion 12 a,12 b are spaced apart relative to one another). Although system 400 isshown implanted in femur 12, system 400 could also be used inconjunction with other bones as would occur to one skilled in the art,including the tibia, humerus, radius, ulna and fibula, to name a few.Additionally, the same components of system 400 can be used to treateither a left or right femur by simply rotating nail 302 180 degreesrelative to axis L₆. Although FIG. 19 illustrates nail 302 implantedwithin femur 12 in a retrograde direction, it is understood system 400may also be implanted with nail 302 in an antegrade direction.

Referring to FIG. 20, therein is shown nail 302, positioning member 304′and bone engaging member 306 as assembled within system 400. Positioningmember 30′ is shown positioned within longitudinal passage 314 andincludes a first portion 402 and a second portion 404. First portion 402includes a threaded upper portion 406 and an elongated lower portion 408extending therefrom along longitudinal axis L₆. Upper portion 406 isconfigured to threadedly engage threaded portion 318 of longitudinalpassage 314. Upper portion 406 also includes a hex recess 410 forreceiving a driving tool (not shown), such as an Allen wrench. Lowerportion 408 has a generally circular body having an outer diameterslightly less than the diameter of longitudinal passage 314. Atransverse passage 412 extends through lower portion 408 and is alignedgenerally perpendicular to axis L₆. The end of lower portion 408opposite its threaded portion terminates in a generally flat surface414.

Second portion 404 has a circular body having an outer diametergenerally corresponding to the outer diameter of lower portion 408 offirst portion 402. Second portion 404 defines an internally threadedportion 416 extending generally along axis L₆ for engaging insertioninstrumentation (not shown). One end of second portion 404 defines agenerally flat surface 418, corresponding to surface 414 of lowerportion 408. The opposing end of second portion 404 terminates in agenerally convex outer surface 420 substantially corresponding toconcave bottom surface 316 of longitudinal passage 314. Second portion404 also defines a transverse opening 422 extending therethroughgenerally perpendicular to axis L₆. Opening 422 is bound by innersurface 424 and is sized to receive bone engaging member 306 therein.

FIG. 20 illustrates a first operational position of system 400.Positioning device 304′ including first and second portions 402, 404) isshown inserted within longitudinal passage 314 of nail 302. Opening 422of second portion 404 is positioned adjacent first end portion 312 a ofopening 312 and generally aligned with opening 312 to define apassageway 426. Bone engaging member 306 is shown inserted throughpassageway 426. Upper portion 406 of first portion 402 is partiallythreadedly engaged within threaded portion 318 of longitudinal passage314. First portion 402 can be rotated by placing a driving tool (notshown) within hex recess 410 and turning first portion 402 in aclockwise or counterclockwise direction. In one embodiment, threadedupper portion 406 and threaded portion 318 each have right-handedthreads. In this embodiment, as first portion 402 is rotated in aclockwise direction, it will be advanced through longitudinal passage314 generally along axis L₆. As first portion 402 is advanced, surface414 will engage surface 418 of second portion 404, therebycorrespondingly advancing second portion 404 through longitudinalpassage 314 generally along axis L₆. As the position of second portion404 is adjusted along axis L₆, inner surface 424 of opening 422 bearsagainst bone engaging member 306 and correspondingly adjusts theposition of bone engaging member 306 along the length of opening 312.

FIG. 21 illustrates a second operational position of system 400 in whichfirst portion 402 is rotated in a clockwise direction until boneengaging member 306 is positioned adjacent second end portion 312 b ofopening 312. It should be understood, however, that bone engaging member306 can be variably positioned anywhere along the length of opening 312.It should further be understood that the terms “first operationalposition” and “second operational position” are not necessarilyindicative of the initial position and adjusted position of boneengaging member 306. For example, bone engaging member 306 couldoriginate in a position adjacent second end portion 312 b and bevariably positioned anywhere along the length of opening 312.

When bone engaging member 306 is positioned adjacent second end portion312 b of opening 312, transverse passage 412 of upper portion 406 willbecome aligned with transverse bore 320 of nail 302, thereby defining apassageway 430. A second bone engaging member 306 can then be insertedthrough passageway 430 to prevent further rotational movement of firstportion 402 relative to nail 302. However, if transverse passage 412 andtransverse bore 320 cannot be aligned to form passageway 430, a secondbone engaging member 306 cannot be used. In this case, in order toprevent first portion 402 from rotating and migrating relative to nail302, a locking set screw can be threadedly advanced along threadedportion 318 of nail 302 until it tightly engages upper portion 406.

Having described selected structural and operational features ofpositioning device 304′, the operational characteristics of system 400will now be described in further detail. Referring back to FIG. 19, nail302 is shown implanted in femur 12 and is anchored to portions 12 a and12 b in substantially the same manner as described above in system 300.Preferably, bone engaging member 306 is initially positioned adjacent ornear first end portion 312 a of opening 312. As first portion 402 ofpositioning device 304′ is rotated in a clockwise direction, boneengaging member 306 is correspondingly repositioned along the length ofopening 312, and more specifically is transferred toward second endportion 312 b of opening 312. Because bone engaging member 306 isanchored to portion 12 f of femur 12, portion 12 f is correspondinglymoved in the direction of arrow “B”, while portion 12 e of femur 12remains stationary, securely anchored to distal end 302 b of nail 302.Thus, portion 12 f of femur 12 is repositioned toward portion 12 e,thereby compressing fracture site 301′. Dashed line 301 b of FIG. 19corresponds to the fractured end of portion 12 f after compression inaccordance with one embodiment of the present invention.

One preferred procedure for implanting system 400 within femur 12 issubstantially identical to the procedure for implanting system 300,except a compression operation as described above is performed insteadof the distraction operation as described in connection with system 300.

The components of systems 10, 100, 165, 195, 200, 300 and 400 may befabricated from any suitably strong, bio-compatible material such asstainless steel, titanium, chrome-cobalt, or any other material whichwould occur to those skilled in the art.

While the invention has been illustrated and described in detail in thedrawings and foregoing discussion, the sane is to be considered asillustrative and not restrictive in character, it being understood thatonly the preferred embodiments have been shown and described and thatall changes and modifications that come within the spirit of theinvention are desired to be protected.

What is claimed is:
 1. A system for treating bone fractures, the systemcomprising: an intramedullary nail having a first end portion opposite asecond end portion along a longitudinal axis, said first end portionincluding an opening extending through said nail and having a firstangled surface aligned at a first oblique angle relative to saidlongitudinal axis; a sleeve configured to fit over said first endportion of said nail, said sleeve including a set of aperturespositioned on opposite sides of said sleeve, said set of apertures andsaid opening aligned to form a first passageway bounded on one side bysaid first angled surface when said sleeve is fitted over said first endportion; and a bone engaging member configured to be slidably receivedwithin said first passageway, said bone engaging member establishing anabutting relationship with said first angled surface when positionedwithin said first passageway.
 2. The system of claim 1 wherein saidopening has a second angled surface generally opposite said first angledsurface to engage said bone engaging member, said first and secondangled surfaces cooperating to define a first pathway oriented at saidfirst oblique angle for said bone engaging member to follow whenreceived in said first passageway.
 3. The system of claim 2 wherein saidopening has a third angled surface aligned at a second oblique anglerelative to said longitudinal axis to engage said bone engaging memberin another abutting relationship when said sleeve is aligned in anotherposition to define a second passageway, and said bone engaging member ispositioned within said second passageway.
 4. The system of claim 3wherein said opening has a fourth angled surface generally opposite saidthird angled surface to engage said bone engaging member, said third andfourth angled surfaces cooperating to define a second pathway orientedat said second oblique angle for said bone engaging member to followwhen received in said second passageway.
 5. The system of claim 4wherein said first and second oblique angles are each about 135 degrees.6. The system of claim 4 wherein said opening extends through said nailand wherein said first and third angled surfaces define a first apex andsaid second and fourth angled surfaces define a second apex oppositesaid first apex.
 7. A bone fracture treatment apparatus comprising: anelongated intramedullary nail having a longitudinal axis and atransverse axis generally perpendicular to the longitudinal axis, saidnail defining a transverse opening therethrough, said opening extendingalong the transverse axis from a first side of said nail to an oppositesecond side of said nail, said opening being bounded by an upper surfaceand an opposite lower surface, one of said upper and lower surfacesdefining a first projection between said first side and said secondside, said first projection extending in a longitudinal direction tonarrow a dimension of said opening along the longitudinal axis, furthercomprising a sleeve with first and second apertures positioned onopposite sides of said sleeve and configured to align with said openingto form a passageway, said passageway following a pathway from one ofsaid apertures to the other of said apertures, said pathway beingoriented at an oblique angle to the longitudinal axis.
 8. The apparatusof claim 7, further comprising a bone engaging member sized to passthrough said passageway and contact said first projection whenpositioned in said passageway.
 9. The apparatus of claim 7 wherein saidnail includes a transverse passage extending at least partiallytherethrough and configured to accept a fastener, said sleeve includes athird aperture configured to align with said transverse passage, saidfastener releasably securing said sleeve to said nail when said fasteneris positioned through said third aperture and into said transversepassage.
 10. The system of claim 9 wherein said nail includes alongitudinal passage extending therethrough, and wherein said fastenerhas a length which does not extend into said longitudinal passage whensaid sleeve is releasably secured to said nail.
 11. A bone fracturetreatment apparatus configured to receive at least one bone fastener,comprising: an elongated intramedullary nail having a longitudinal axisand a transverse axis generally perpendicular to the longitudinal axis,said nail defining a transverse opening therethrough, said openingextending along the transverse axis from a first side of said nail to anopposite second side of said nail, said opening being bounded by anupper surface and an opposite lower surface, each of said upper andlower surfaces defining a respective upper and lower projection betweensaid first and said second side, said upper and lower projectionsextending in a longitudinal direction to narrow a dimension of saidopening along the longitudinal axis; said upper projection having afirst portion extending at a first angle with respect to said transverseaxis, said lower projection having a second portion extending at asecond angle with respect to said transverse axis, said first portionand said second portion substantially parallel and spaced a firstdistance along said longitudinal axis to define a first passage throughsaid transverse opening.
 12. The apparatus of claim 11, wherein saidupper projection includes a third portion and said lower projectionincludes a fourth portion, said third and fourth portions in substantialparallel alignment and spaced a second distance along said longitudinalaxis to define a second passage through said transverse opening.
 13. Theapparatus of claim 11, wherein said transverse opening has a firstlength and further including a bone fastener having a width and alongitudinal length, said width substantially equal to said firstdistance and said longitudinal length substantially greater than saidfirst length.
 14. A system for treating bone fractures, the systemcomprising: an intramedullary nail defining a longitudinal axis and atransverse axis generally perpendicular to the longitudinal axis, saidnail defining an opening therethrough along the transverse axis, saidopening being bounded by a bearing surface; a sleeve defining a pair ofapertures on opposite sides of said sleeve, each of said aperturesdefining an engaging surface, said apertures and said opening aligned toform a passageway when said sleeve is fitted over said nail; a boneengaging member sized to pass through said passageway; and means forbiasing said sleeve in a longitudinal direction to firmly engage saidengaging surface of at least one of said apertures against said boneengaging member and clamp said bone engaging member to said bearingsurface of said opening.
 15. The system of claim 14 wherein at least oneof said nail and said sleeve define an internally threaded portion, saidbiasing means includes an end cap, said end cap defining externalthreads to engage said internally threaded portion of said one of saidnail and said sleeve to thereby bias said sleeve in a longitudinaldirection.
 16. The system of claim 15 wherein said nail and said sleeveeach define an internally threaded portion, said end cap including athreaded end portion, a threaded intermediate portion and an enlargedend portion, and wherein said threaded end portion engages saidinternally threaded portion of said nail and said threaded intermediateportion engages said internally threaded portion of said sleeve tothereby bias said sleeve in a longitudinal direction.
 17. The system ofclaim 15 wherein said end cap includes a hex broach to receive a drivingtool.